Recombination between the dfrA12 -orfF- aadA2 Cassette Array and an aadA1 Gene Cassette Creates a Hybrid Cassette, aadA8b

Recombination between the dfrA12-orfF-aadA2 cassette array and an aadA1 gene cassette creates a hybrid cassette, aadA8b.

Homologous recombination between closely related gene cassettes, such as aadA1 and aadA2, which are 89% identical, can create hybrid cassettes and hybrids of existing cassette arrays. A new cassette array, dfrA12-orfF-aadA8b, which was created by such a recombination event occurring within the aadA2 cassette in the dfrA12-orfF-aadA2 array, has been identified.

Widespread presence of dfrA12 and its association with dfrA12-aadA2 cassette in Salmonella enterica isolates from swine.

One hundred and eighty-nine Salmonella isolates from swine were tested for susceptibility to nine antimicrobial agents, presence of dfrA12 and class 1 integrons containing dfrA12-orfF-aadA2 cassette. All isolates were multidrug resistant and exhibited highest resistance prevalence to trimethoprim (93%). Most isolates (89%) were intll-positive and 107 isolates (57%) carried dfrA12, all of which ...

Characterization of antimicrobial resistance patterns and integrons in human fecal Escherichia coli in Taiwan.

Two hundred and twenty-five fecal strains of Escherichia coli isolated from 109 non-hospitalized adults in 2006 were investigated for susceptibility to antibiotics and for the presence of integrons. High resistance rates in fecal strains of E. coli were observed for streptomycin (52.0%), ampicillin (50.2%), piperacillin (50.2%), trimethoprim/sulfamethoxazole (47.6%) and chloramphenicol (33.8%)....

Dynamics of a Class 1 Integron Located on Plasmid or Chromosome in Two Aeromonas spp. Strains

Integrons are non-mobile bacterial genetic elements that carry different cassettes conferring antibiotic resistance. Cassettes can excise or integrate by action of an integron-encoded integrase, enabling bacteria to face environmental challenges. In this work, the functionality and dynamics of two integrons carrying the same cassette arrangement (dfrA12-orfF-aadA2), but located on plasmid or ch...

Correctly identifying the streptothricin resistance gene cassette.